Definition web: Virus
Any of various primitive, submicroscopic parasites of plants, animals, and bacteria that often cause disease. They consist essentially of a core of RNA or DNA surrounded by a protein coat. They are unable to replicate without a host cell, and so viruses are typically not considered living organisms.
Viruses are commonly detected and measured using plaque assays.
See also: Viral plaque assays
Amy A Allen | SciWeb | Immunology research analyzers